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This paper presents numerical simulation results of cylindrical steel lining‐concrete structure’s dynamic plastic response under internal intense blast loading by ANSYS/lS‐DYNA finite element software. The emphasis is put on the dynamic plastic deformation and three‐dimensional stress conditions of steel lining‐concrete structure. It is shown that maximal plastic deformation of steel lining‐concrete structure results from the first action of shock wave on internal surface of the structure. For the steel lining of the structure, radial stress is compressive stress, while hoop and axial stress is tension stress. For concrete of the structure, three‐dimension stress is compressive stress near the out surface of steel lining. Radial stress of concrete at intense shock wave seems to decay as an exponential function with increasing of scaled‐distance.

Although the wind of change is blowing strongly through the gas industry a substantial proportion of the gas, for some time to come, will be made by coal carbonisation and by carburetting water gas. Even these more conventional methods will be subject to change such as the choice of lower‐rank coals to produce reactive smokeless solid fuels and the use of light Hydrocarbon oils, such as primary flash distillate, in place of gas oil. This article deals with some of the corrosion problems that arise in these more established types of plant.

The contribution of epoxy resin‐based surface coatings towards reducing the annual cost to the nation of the effects of corrosion has been appreciated by the paint chemist/technologist, and is being increasingly recognised by engineers, designers and authorities whose task it is to specify special paint systems for protection or decoration. This article surveys the properties and successful applications of these coatings.

The behavior of joints has a significant effect on the stability of water conveyance tunnel. The purpose of this paper is to study the contact and friction at the joint of the tunneling segment lining and establish its contact friction model. At the same time, the stress and deformation characteristics at the joint of the segment under hydrostatic load are analyzed.

In this study, the contact and friction in a bolted joint are examined using shear testing. The feasibility of the proposed model is verified by a numerical simulation of tests and a theoretical analysis. Accordingly, the effect of joints on the lining is explored under internal hydrostatic loading.

The results show that the openings of tunnel segments in joints gradually expand from the positions of the inner and outer edges to the location of the bolt. Moreover, the stress concentration zone is formed at the bolt. Under hydraulic loading, the opening displacement at the joint increases as the water pressure increases; nevertheless, it does not exceed engineering requirements. When the water pressure of the tunnel lining joint reaches 0.5 MPa, the opening of the joint slowly increases. When the water pressure exceeds 0.7 MPa, the opening of the joint rapidly and significantly increases.

Contact and friction in a bolted joint were examined using shear testing. A cohesive zone model of bolted joints was proposed based on test results. The influence of joint behavior on the stability of water conveyance tunnel was studied.

The Reprocessing Engineering Division of British Nuclear Fuels undertakes the design of nuclear chemical plants for construction and subsequent operation at the Sellafield Works of the Reprocessing Operations Division. Plant construction cannot take place until it has been demonstrated that the chosen design will allow the plant to operate in an adequately safe manner, corresponding to an extremely low level of risk. Risk, or the cumulative frequency and consequences of all potential hazards, is evaluated by means of probabilistic risk assessments (PRA).

This work affords a practical checklist that specifies the civil engineering trades-related hazards and offers a safety indicator to identify the safety level of a construction project concerning the hazards of the civil engineering trades.

The methodology depends on reviewing the archival works, visiting the construction sites, utilizing the direct observation and preliminary hazard analysis methods and conducting semistructured interviews to pinpoint and validate the checklist of the civil engineering trades-related hazards. Additionally, a questionnaire-based survey with the rank sum weight technique has been employed to assemble and analyze the data required to build the safety indicator.

Relying upon the used methodology, 70 hazards under the trades of general environment, earth, demolition, excavation, concrete, dewatering, waterproofing insulation and scaffolding have been pinpointed and validated. This is in addition to the safety level indicator of the civil engineering trades-related hazards (SLICETH), which indicates high viability during its validation in five national and international projects.

The value of this work lies in its ability to tackle the gap existing in the safety management knowledge regarding the notion of the hazards of the civil engineering trades and their influences on the safety performance of the construction projects. As a result, it offers a complete knowledge to the academics and the practitioners for confronting the negative impacts of the civil engineering trades-related hazards. Consequently, it helps in enhancing the safety performance level in the sites of the construction projects.

The purpose of this paper is to investigate the process optimization of a precast concrete component production line by using value stream mapping.

This paper is an empirical focused on of lean production theory and value stream mapping. The data in the case study were collected in real time on-site for each process during the production process of a prefabricated exterior wall.

The results of the current value stream map indicate that the main problems of the current production process are related to equipment, technology and organization. The equipment problems include simple demolding and cleaning tools and the lack of professional transfer channels. The technology problems include the lack of a marking mechanism and pipeline exit mechanism. There is a lack of standard operating procedures and incomplete process convergence. A comparison and analysis of the current value stream and the future value flow indicate that optimizations of the process flow, the production line layout, and the standard operating procedures have shortened the delivery cycle, reduced the number of workers, improved the operator’s operating level and balanced the production line.

The results of this study provide practitioners with a clear understanding of the optimization of the precast concrete component production and represent a method and basis for the process optimization of a factory production line; the approach is suitable for process optimization in other areas.

This research represents an innovative application of lean production theory and value stream mapping in a complex production line of precast concrete components and thereby fills the gap between the theory and practice of the optimization of a precast concrete component production line.